Conventionally, rain and dirt are typically removed from vehicle backlites (i.e., rear windows) using a rear wiper(s), especially in sport utility vehicles. Unfortunately, rear wipers tend to be rather fragile, costly and prone to damage.
In view of the above, it is apparent that there exists a need in the art for a system and corresponding method for removing rain and/or dirt from vehicle backlites without the need for use of a rear wiper.
Rear spoilers for directing air/wind onto vehicle backlites are known in the art. For example, see U.S. Pat. Nos. 4,674,788, 4,881,772 and 5,845,960, the disclosures of which are hereby incorporated herein by reference. The '788 patent discloses a rear spoiler which may be manipulated between two different positions. FIG. 1 is a perspective view of vehicle 3 including the '788 rear spoiler 5 mounted thereon. In the first position, spoiler 5 diverts air flowing along upper vehicle body surface 7 (i.e., roof) upwardly so as to exert a downward force and enhance traction of vehicular wheels 9. In the second position, spoiler 5 guides air flow toward a rear window (i.e., backlite) 11 surface so as to remove rain water, dust and so forth from the major exterior surface thereof.
Unfortunately, the system of the '788 patent is less than desirable for at least the following reasons. First, while the spoiler may guide air flow toward the backlite, it does not serve to accelerate the speed of the air flow. Thus, when the vehicle is traveling at rather slow speeds (e.g., 20 mph), the air flow will often be insufficient to clean/remove rain and the like from the surface of backlite 11.
Second, the backlite appears to be of conventional glass in the '788 patent (the contact angle .theta. of conventional uncoated soda lime silica glass is about 22-24 degrees). As a result, even when air is caused to flow across the surface of the backlite, rain may not be sufficiently removed therefrom due to the inherent tendency of glass to hold water on its surface due to its naturally low contact angle .theta..
The '772 and '960 patents also disclose rear spoilers designed to direct air flow toward backlites. Unfortunately, the '772 and '960 patents suffer from the same problem as the '788 patent in that the backlite appears to be of conventional glass thus having an inherently low contact angle .theta.. As a result, even when air is caused to flow across the surface of the backlite, rain may not be sufficiently removed therefrom due to the natural tendency of glass to hold water on its surface due to its inherently low contact angle .theta..
It will be apparent from the above that there exists a need in the art for a system and/or method for efficiently removing water (e.g., rain) from the exterior surface of a rear backlite.
It is a purpose of different embodiments of this invention to fulfill any or all of the above described needs in the art, and/or other needs which will become apparent to the skilled artisan once given the following disclosure.